Histologic and Clinical Evaluation of Ridge Augmentation of Extraction Sockets with Severe Bone Defects: A Clinical Prospective Study.

PURPOSE: To primarily evaluate the dimensional changes of bone and soft tissue following ridge augmentation in compromised molar regions. The secondary objective was to evaluate the histologic composition of augmented sites. MATERIALS AND METHODS: The study included 27 patients who underwent augmentation of extraction sites with grafts covered by a collagen membrane. CBCT was taken immediately after augmentation (T2) and after 8 months of healing, before implant placement (T3). The width and height of the extraction sites were recorded at extraction (T1) and reentry surgery (T4). A histomorphometric analysis was performed. Data were evaluated in terms of bone crest level, implant survival rates, and change in mucogingival junction. RESULTS: According to clinical measurement, horizontal and vertical bone gain was 10.15 ± 1.00 mm and 8.80 ± 1.86 mm, respectively. Radiographic measurement showed that the horizontal width changes were 1.46 ± 0.52 mm, 0.98 ± 1.29 mm, and 1.29 ± 0.82 mm, respectively, at 1, 3, and 5 mm apical to the crestal level. Vertical bone change was 2.34 ± 0.90 mm in the center of the socket. Histomorphometric analysis showed that percentages of mineralized bone, nonmineralized tissue, and bone substitute were 32.31% ± 13.25%, 25.36% ± 12.24%, and 42.34% ± 9.54%, respectively. The mucogingival junction shift was 0.6 ± 1.1 mm. Implant survival rates and crestal bone resorption were 100% and 0.78 ± 0.58 mm, respectively, after 1 year of loading. CONCLUSION: Ridge augmentation can be performed successfully to manage extraction sockets. Membrane coverage combined with primary wound closure could be conducive to new bone regeneration and peri-implant tissue health.